Aligning method



Aug. 11,1942. A, PjPETERs 2,292,968

ALIGNING METHOD Filed Jurie- 10, 1939 s Sheets-Sheet 1 INVENTOR, ALBERT I? PETER:

ATTORNEY.

Aug. 11,1942. A, P, PETE S 2,292,968

' ALIGNING METHOD I Filed June 10, 1939 5 Sheets-SheetZ INVENTOR. A1. 55m" P PETERS ATTORNEY.

Aug. 11,- 1942. A. P. PETERS ALIGNING METHOD Filed June 10, 1939 5 Sheets-Sheet 3 INVENTOR; v

'A' LBERT E PETERS ATTORNEY.

8 1942- r A. P. PETERS 2,292,968

ALIGNINQ METHOD Filed'Jt lne 1o, 1959 5 She ets-Sheet 4 :4. u ix 1 4 1M INVENTOR.

' ALBERT P PETEKS ATTORNEY.

Aug. 11, 1942. A, p. s 2,292,968

. ALIGNING- METHOD Fi1ed June 10, 1939 5 Sheets-Sheet 5 I INVENTOR.

ALBERT PETERS ATTORNEY.

f Patented Aug. 11, 1942 OFFICE ALIGNING METHOD Albert Peters, San Francisco, Calif.

Application Junev 10, 1939, Serial No. 278,507

" 1 Claim.

This invention relates to an aligning method and device. I

Anobject of this invention is to provide a method whereby the relative positions of parts of a machine or the like, or the alignment of parts of a vehicle, such as the wheels and wheel supports can be determined constantly during the assembly and adjusting operations.

Another object of this invention is to provide a method for accurately indicating the positional characteristics of parts of. a machine, such as the wheels or mountings of. a vehicle, in such a manner as to show any misalignment and also the probable cause of any deviation from normal alignment of said parts.

Another object of this invention is to provide an aligning device which can be easily attached I and detached to the parts of a machine for indicating relative alignment; particularly the device may be attached by magnetic clamps so arranged asto maintain the device'in a predetel-mined position relatively to machine or vehicle.

A further object of this invention is to provide a method and device wherein the relative alignment of parts of a machine, such as the assembly of vehicle parts, or wheel alignment and the like, is readily indicated by the relative position of light rays orbeams or the like.

A further object of this invention is to provide a method and device wherein light rays are directed in a predetermined relative direction for indicating relative positions of machine parts, the direction being accomplished by easily detachable mountings, preferably by magnetic clamps to hold the light directing elements in selected positions.

Particularlyit is an object of this invention to provide a method and device for the assembly of parts and mountings of a vehicle through level or relative attitude indicators magnetically held in place.

A further particular feature of this invention is to provide a method and apparatus wherein alignment and adjustment are accomplished by automatic constantly visible indication of relative attitude of the respective 'parts without requiring dismantling, repeated manual tests, and measurements of the relative position of parts; the indication being accomplished by the reflection of light rays onto a tabulated surface from a definite position of the parts to be tested relatively to said surface so that an. enlarged and sometimes exaggerated indication of the relative attitude of said parts can be observed on the the parts of said surface at all times while the work of assembly or aligning is continued uninterrupted: the surface being so graduated and arranged as to coact with the projected light rays to indicate by the nature of the path described by the light rays or light beams the characteristics of alignment that may influence a given attitude of the relative parts.

Another object of this invention is to provide an aligning method and device whereby the degree and cause of misalignment of the wheels of a vehicle can be determined speedily by the behaviour of a light ray or light beam relatively to a graduated surface. g 7

Other objects of this invention are to provide an aligning method and device that will be superior in point of simplicity, inexpensiveness of construction, positiveness of operation, facility and convenience in use and general efficiency.

Other objects of the invention together with the foregoing will be set forth in the following description of the preferred method and the preferred embodiment of means for practicing the same, which is illustrated in the'drawings accompanying and forming part of the specification. It is to be understood that I do not limit myself to the embodiment disclosed in said de-- scription and the drawings as I may adopt variations of my preferred forms within the scope of my invention.

With the foregoing and other objects in view, which will be made manifest in the following detailed description, reference is had to the accompanying drawings for the illustrative embodiment of the invention, wherein:

Fig. l is a plan view ofthe arrangement of the coacting surfaces and devices with respect to an automobile for performing my aligni method.

Fig. 2 is a side view of the boards or surfaces with the automobile in place therebetween.

Fig. 3 is a front view of a graduated surface showing the path of the light ray travel thereon when the wheels are turned in opposite directions.

Fig. 4 is aside view of a wheel with my light direction device shown in section thereon.

Fig. 5 is an end view of the wheel with the light direction aligner device thereon.

Fig. 6 is a side view of a magnetically clamped aligning device.

Fig. 7 is an end view of the magnetically clamped aligning device.

Fig. 8 is an end view of a modified form of the device.

Fig. 9 is an end view of another form of my device.

Fig. 10 is an end view of the mounting oi my device on a drum after the wheel is removed;

Fig, 11 is a side view of the device mounted on the brake drum.

Fig-12 is a perspective diagrammatic view of the device on a wheel in relative position to the graduated surface so as to indicate thereon Fig. 18 is a front view of the graduated surface showing the indications for the toe-out and turning radius.

Fig. 14 is a plan view of the steering rod assembly the adjustment or bending of which influence the toe-in," toe-out" and turning radius. r

Fig. 15 is a front view of the graduated surface showing the lines of travel of the light beam on the surface at various alignments of the compound adjustment for caster and king pin inclination.

Fig. 16 is a sectional view showing the king pin inclination indicated on the diagram in Fig. 15.

Fig. 17 is a side view of the steering knuckle showing the axis podtion causing the caster indicated on the diagram in Fig. 15.

Fig. 18 is a diagrammatic view of the step wherein the light beam are used in assembly for aligning the frame or chassis and position of wheel mounting.

Fig. 19 is a atic view showing the use of a level instrument for aligning the wheel and axis assembly.

Fig. 20 is a top plan view of the wheel alignment relatively to a graduated surface outside of the vehicle. I

Fig. 21 is a side view of an instrument having double levels on a magnetic clamp and also a projector thereon,

Fi 22 is an end view of the instrument shown in Fig. 21.

My method in general includes the steps of assembling the parts of a machine by the use of a leveling indicator held magnetically on a desired part. At a certain stage of the assembling operation the aligning adjustments are made by means of a ray or beam of light projected upon a graduated screen from a predetermined position relatively to the screen. The relative attitude of said parts can be ascertained by observation from a distance and the parts can be adjusted until the indication on the graduated screen corresponds to a desired alignment.

In detail my method includes the steps of preferably magnetically attaching a light projecting element to a part of a machine, for instance to the chassis of a vehicle or automobile, so as to point or project the light beam to another part of the chassis where another part, such as the axle must be assembled in direct line with said light beam. The assembly can be accurately performed at the point constantly located by the fixed beam of light. Then for relative alignment of parts of such assembly calibrated levels are magnetically located and held on the brake drum. By the us of such calibrated levels the steeringgear is adjusted and the various adjustments such as the camber, caster, king pin slant and the like are roughly set. Then final adjustments are checked and achieved accurately by the projection of light beams from said parts unto a graduated screen outside of the vehicle in such a manner that any thereof supported a light projector 2 directed forwardly to the desired location of the ends of the front axle 3. This step may be also used for straightening the frame of the vehicle by detecting distortions of parts of the frame from straight aligned position as indicated by the light beams.

The second step is illustrated on Fig. 19 wherein the levels 4 are magnetically attached to a brake drum I so as to allow rough setting of the wheel and steering gear mounting during assembiy.

The third step is illustrated on Fig. where after the assembly and rough setting of the wheels the light projectors magnetically held on 20 the wheels project beams of light, preferably in the form of line point or hairline shape light rays unto a spaced screen 8 and final adjustments of the wheel and its mounting are made to correct errors or misalignments indicated by the position 25 or path of the light beams on the graduated screen.

In the event of testing or aligning wheels the same can be accomplished without dismantling or measurements on the floor. The automobile is located on a graduated base or floor chart I so that its wheels are at a definite distance from the screens 8, then a light beam is projected from the rear wheels to the front axle or wheels to check the alignment with the front wheels. Then 5 light beams are projected from each of the front wheels onto the screen 8 so that the paths of the light beams at a complete turn of the wheels in either direction relatively to said graduated base 'l are projected on the graduations of the screen 40 indicating the relative attitude of the wheels.

It is part of my method to so project the light rays or beams from the front wheels that the camber of the wheel is truly shown relatively to vertical and horizontal markings, and so that the caster misalignment is evidenced by distortion horizontally and king pin ent by distortion vertically with relation to corresponding horizontal and vertical coordinates of the graduations on the chart or. screen 0. The

5 toe-in," "toe-out and turning radius, are indi cated by the balance of the increase of distance at turns to both directions between the light beams projected from front wheels. By first charting the path of projected light beams on a screen 6 corresponding to normal alignments,

deviations from that chartered path indicate misalignment, and according to the direction and angle of deviation the cause of misalignment can be determined with certainty without'dism mounting the wheels or measuring the wheel positions, wheel mountings or steering gear assembly. It is preferable that the light beams be projected from ma netically held source easily and accurately maintained in position on the part to be tested.

The apparatus for carrying out my method includes the graduated base or floor chart I on which the automobile 8 is located on a predetermined graduation line corresponding to a given type of vehicle. Aligned with the center 'line 9 of the graduations of the base I is the screen i which has a central panel II and sides or wings I! preferably hinged at H so as to be adjustable to desired angles. Fastening strips It, or other suitable latches, hold the wings it ing of the projected light beams.

to the horizontal clamps.

in their adjusted angular positions relatively to the central panel The anel II and the wings l2 are provided with vertical and horizontal graduations I5 spaced at a given spacing to permit readings corresponding to actual relative attitude of the wheels l8 of the automobile 3 located at a predetermined distance from the screen 6. There may be charts provided on the screen 6 indicating the normal location or path of light projection for a given type or model of vehicle with which the behaviour of the corresponding type or model of vehicle under test can be compared. Markingsfor normal points relative to which adjustments may be made can bealso pinned, or hanged on suitable hooks or the like on the charts or screen 8.

The projector 2, in the illustrative form herein includes a tube H in one or both ends of which is an electric light socket |3 suitably connected to a source of electricity; A suitable light globe I3 is in the socket I3. Around the. light globe I9 is a reflector 20. In front of the light globe I9 is a shade 2| which has an opening for the transmission. of light rays in a selected shape of beam or beams. For instance the shade in the form shown in Fig. 8 has so called-cross hair 3 slots 22, and the shade shown in Fig. 9 has spaced point apertures 23 to transmit light rays reflecting dots on the screen 6. In the extreme end of the tube l! are lenses 24 in a suitable casing 25 so as to be adjustable for proper focus- Similar projection units are provided in both ends of the tube H as shown in Fig. 4, projecting light beams in opposite directions.

The projector 2 is mounted on a bracket which has three clamps 26 adapted to clam over the tire of the wheel It at two horizontally opposite points and at a point at the top at right angles Aligning plates 21 hold the bracket in a plane substantially parallel with the plane of the wheel l6.

For quick and accurate adjustment it is preferable that the projector 2 be magnetically clamped and held in place as shown in Figures 6 and 7.

In the illustrative embodiment of magnetic clamping of the projector 2 are shown three permanent magnets 28, each of which has a tubular hub 23, fitting over the tube l1, and legs 30 spread at an angle but having ends 3| leveled sub-' stantially parallel with the axis of the tube 11.

. In this manner when the magnetic clamps are engaged with a surface of the part to be tested the projector 2 is automatically aligned with the surface so engaged. Inasmuch as the legs 33 are of such length that all the ends 3| thereof are aligned with each other the projector is held parallel with the surface engaged by its magnetic clamps. In some instances, such as for certain indications of so called toe in adjustment, magnetic spacer washers 32, as shown in Fig. 6, may be interposed between the ends 3| of the legs 30 near one end of the projector 2, and correspond.- ingly narrower washers 33 placed below the ends 3| of the legs 30 of the middle clamp 28 so as to hold the projector 2 at a predetermined outwardly diverging angle relatively to the surface of the wheel l6 so that as the beams of light projected from the projectors 2 on the front wheels |6 of the vehicle are parallel then the wheels l6 are actually adjusted to a degree of spacer washers 32 and 33. The magnetic clamps magnets 23 point with their legs 30 toward the surface to be tested. The direction of the legs 33 may be reversed by placing the end magnets 23 on the tube l'l so that the legs 30 converge toward the middle of the projector 2. Thus the same clamps 28 may be used to clamp on larger or smaller surfaces.

While the magnetic clamping and adjusting of the projector 2 is always preferable, yet in some instances the existing bolts or bolt holes may be utilized for fastening the projector 2 in place. For instance a specific application of the projector on a brake drum 35 when the wheel is dismounted is illustrated in Figures 10 and 11. The projector tube I1 is supported onbrackets 36 the ends of which are held by the usual bolts 31' in the usual bolt holes 38 of the brake drum 35. The aperture 39 in the ends of the brackets 36 are elongated to permit the use of the brackets within certain variations of bolt hole spacings on the brake drums 35. An added spacer bracket 40 mounted on the spindle further assists in aligning the projector 2 in place.

It is to be noted that the tube H of the projector 2 has a pair of bubble levels 4| (Fig. 6)

located at right angles to each other whereby the use of levels in adjusting is combined with the light beam indications for accuracy. This also facilitates the accurate location of the projector 2 at a desired angle. A device which may be used throughout all the steps of the method is illustrated in Figures 21. and 22. In this device a bracket 42 is provided with magnetic clamps 43. On the bracket 42 are supported calibrated levels 44 and 45 of the usual structure at right angles to each other so that the levels so supported can be easily clamped on any part to be worked on. Certain adjustments can be roughly set in this manner. This device would be used during, assembly when the adjustments are not set with complete accuracy. For the final checking and adjusting the projector 2 heretofore described is inserted into a socket 46 provided in said base bracket 42 and is held therein by suitable set screws 41. Thus the same device combines in itself both the usual type of level and the new light projector for preliminary and final adjustments respectively.

In operation, for instance in connection with vehicle wheels, the axles, knee action units, or independent wheel suspensions are to be first bolted or attached to the frame. In order to on each side of the frame I. The opposite light beams are placed some distance back of the location of the wheel assembly and areequally aligned position relatively to the frame I when 28 are held in adjusted positionon the tube |1 by means of suitable set screws 34 so that all the aligned on each side of the frame I. The beam of light is thus fixed in this illustration by, the

symmetrical mounting of the projectors 2 on the opposite sides of the frame I as shown in Fig. 8 so that the light beams point to the desired location of the units to be mounted at the front end of the frame. The axles, knee action units, or independent wheel suspension are in properly the light beams projected from the projectors 2 point directly upon said mountedv units.

On the usual front wheel I6 of the automobile 8 the wheel spindles, hubs and brake drums are then attached. ,In the adjusting of these parts to a proper caster, camber and king pin slant the levels are used on suitable platforms or brackets attached to the parts worked on preferably by magnetic clamps. Thus these approximate adiustments are achieved before the wheel is atchart 6. By manipulating the wheels II in the manner of their actual operation the location and path of the light beams on the graduated chart 8 gives accurate indication and reading of the camber, toe-in, caster, the rise and fall of the wheels, the steering angle, the kingpin slant. the included angle, turning radiusor other behaviour of the wheels I when they are turned in either direction. This is accomplished by the setting of the wheels on a predetermined line on the base or floor chart I, which renders the readings on the wall chart or screen i accurate. The mechanic does not need to check instruments or remeasure the various units worked on. The beam of light on the screen or chart changes location as the mechanic is making the adjustments and indicates the setting.

An example of necessary adjustment is the camber of the wheels. The front wheels of a easily. This camber is usually given to the steer-' lng knuckles and spindle ,by tilting the steering knuckle so that the steering knuckle is at outwardly and upwardly spread angle instead of being perfectly vertical. In Fig. 12 the vertical line of the cross hair line is parallel with the wheel It. The cross like beam 4| appears at an angle to the vertical graduations on the screen 6. If the camber is lost or is not of proper angle, then the mechanic can adjust the axle, or the knee action support, or the like mounting. until the vertical line of the cross beam on the screen 6 is at a desired angle or camber.

Another example of adjustment of the front wheels is the so-called toe-in which is an adjustment to oii'set the wearing action on the tires by the camber, and to produce more even wear on them. This refers to the converging of the front wheels toward each other at the front. An additional reason for this adjustment is that when the vehicle is running at high speeds, the wheels have a tendency to toe-out." If toed-in too much, or not enough, the treads of the tires will grind. The toe-in is checked in my method and device by attaching to the front wheels I the projectors 2 so as to reflect a light beam onto the screen or chart I5. Then the spacers l2 and 33 are placed under the legs ll of the magnets II as heretofore described so as to diverge the light beams relatively to the plan of the wheels I to the desired angle of toe-in. By adjusting the wheels until the light beams are. parallel the desired toe-in is set.

The so-called toe-out and the turning radius of the front wheels it are closely related to the toein adjustment of the wheels. these adjustments can be easily checked by the varying distance between the reflections of the As shown inFig. l3

light beams on the chart or screen s as the wheels tances in opposite directions should balance for equal toe-outs and turning radii. The initial points where the light beams appear on the chart or screen 6 are denoted herein by the letters R and L indicating respectively the renections of the light beams projected from the right and left wheels of the vehicle. The distance on the chart between the projected beams is denoted on Fig. 13 by the letter A. Then the wheels II are turned fully in one direction, for instance toward L in Fig. 13. At the extreme turn the distance between R and L is as denoted by the letter B which by reason of the compensating turning radius is larger than the distance A. Then the wheels are turned in the other direction and at the end of the full turn the distance between the points L and R is as denoted by the letter C which is also usually larger than the initial distance A.

Any difference between the distance B and C at the respective extreme turns of the wheels It indicates an unbalanced condition. The mechanic can make the adjustments until the respective extreme distances are balanced by observing the reflections on the screen 6, without the need for repeated measurements.

The toe-in adjustment is usually dependent on the cross steering rod 49, and the toe-out and turning radius adjustments are usually dependent on the steering arm II, a diagrammatic assembly of which is shown in Fig. 14. The toe-in is usually adjusted by adjusting the length of the cross steering rod or tie rod is from one steering knuckle to the other. If this does not correct the adjustment then it may be necessary to straighten a bending of the axle 3 or of the spindles. The most common cause of discrepancy in the adjustment of the toe-out or turning radius is that one of the steering arms Si is bent. Therefore thisdiscrepancy can be corrected by straightening the steering arm 5| until the relative distance between the light beam points R and L is of the desired balanced length.

Another common and important adjustment is the adjustment of the caster of the front wheels. This adjustment is an upward and rearward incline of the steering knuckle 52, as shown in Fig. 17, so that the steering axis 53 therethrough meets the ground in advance of the point of contact of the wheel. The vertical axis It in Fig. 17 points substantially toward the point 'of contact of the wheel at the bottom. Thus the front wheels II are purposely placed out of perpendicular, or castered, in order to bring the point of contact between tire and road more directly under the steering spindle 55. Due to this offset from the perpendicular the wheels 16 rise and fall as they are turned in the respective directions. Another adjustment which manifests itself in the rise and fall of the wheels while being turned is the inclination of the king pin 58 as shown in Fig. 16. This so-called' king pin slant is sidewise and inward of the. vehicle at the by one or another of the component causes of said rise and fall. For instance viewing Fig.

.components of the paths of light indicate the relative caster alignment. when the king pin inclination is increased above the normal angle of inclination then the path is distorted upwardly from normal as shown by the paths 58 on Fig. 15. A straightening of the king pin position relatively to the vertical and outwardly causes a distortion of the lightbeam paths downwardly asshown on the paths 59 below the normal paths 51. On the other hand it was found that the horizontal distortion of said paths SI and 59 corresponds to a misalignment of the angle of caster. Itiis important that the caster and king pin inclination of the front wheels be equalized, and this characteristic is quickly ascertained and corrected by observing therelative paths of the f light beams projected onto the screen. The mechanic can change the adjustments, or tiltthe axle, or bend the knuckle, while observing the light beam on the chart until the light beams indicate equalization and correction of the adjustments on both front wheels I 6.

It is to be noted that there is a certainamount of trave1 of the wheels l8 during turning even whenthe vehicle is otherwise stationary and this travel would cause further distortion of the path which might be misleading in some instances. It is therefore desirable that during the checking of any adjustments that require turning of the wheels, .the front wheels be either. off the ground or be supported on suitable swivel plates, so that only thetrue rise and fall caused by the wheel mountings is indicated on the screen or chart.

The alignment of the rear wheels with the front wheels is also readily ascertained by projecting light beams from the rear wheels to the front wheels in alignment with the projectors 2 on the front wheels. When the light beams coincide then the rear wheels are properly aligned with the front wheels. The mechanic can make his adjustments in case of misalignment until the light beams from the rear wheels are brought into directional coincidence with the light beams from the front wheels.

The wings I! of the screen 6 are preferably always .set so that they are substantiallyat right angles to the beams of lightwhen the wheels arein extremely turned positions. The charts IS on the screens 8 are graduated and marked to indicate the true distance of distortion relatively to a set point or line on the fioorchart I. If so desired the rear wheels may be checked by rearward projection of light beams on a rear screen 8 as shown in Fig. 1-. Screens or charts may be employed in other relative positions, such as at one side or-both sides of the vehicles. In such arrangements the graduations must be tabulated to allow for lateral reading of variation of light paths-corresponding to certain adjustments.

The characteristics of wheel location and movements responsive to certain adjustments are thus reproducedon an enlarged scale in readily observable position. The instruments are quickly and easily attachable to the parts to be checked. The magnetic clamps fasten securely and accurately.

It was found that each adjustment or irregularity of the wheel mounting'causes a characteristic distortion of the position and path of the light beams projected from the wheels. These characteristic variations can be charted for various types-of vehicles. and the vehicles can be quickly tested relatively to such chart. The characteristic deviations from such normal chart deflnitely determine and indicate the cause of the misalignment without necessitating complicated measurements and without dismantling the wheels, the'steering gear, or mountings. By coaction with the floor chart I each type of vehicle can be accurately lined up at a predetermined distance from the wall chart or vertical screen 8. The indication by the light beams remains constantly observable while the mechanic.-

makes the adjustments obviating the need for "repeated stopping of the work for measurements The diagnosis and adjustments of V claim and desire to secure by Letters Patent is:

In a method of adjusting the alignment of a steerable vehicle wheel relative to the vehicle by visual reference during steering movement of said wheel to the path delineated by the point of interception of a beam of light projected from said wheel in fixed relation thereto onto a vertical surface having indicia thereon denoting standard steering characteristics for said wheel, the steps oi performingsuch adjustment of said alignment while projecting said light onto said surface and effecting such adjustment as is shown to be necessary by visual reference to the relation between the delineated path and said indicia until'the path of said point of interception when I said wheel is steered coincides with said indicia Y on said surface denoting standard steering characteristics for said wheel.

ALBERT P. PETERS. 

